Investigation of tungsten solubilization from waste W-based catalyst and leaching kinetics in water-free green solvents
JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS, cilt.189, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 189
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.jtice.2026.106877
- Dergi Adı: JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Applied Science & Technology Source, Chemical Abstracts Core, Compendex, INSPEC, Engineering Source (EBSCO)
- İstanbul Üniversitesi-Cerrahpaşa Adresli: Evet
Özet
Background: Spent Ni-W hydrocracking (HYC) catalysts represent a significant secondary resource of critical metals such as Ni, W, and Al. However, conventional acid leaching of tungsten is hindered by the formation of insoluble tungstic acid, limiting recovery efficiency. This study addresses this challenge and investigates a sustainable alternative for metal recovery from end-of-life HYC catalysts. Methods: A choline chloride-p-toluenesulfonic acid (ChCl:PTSA)-based leaching system was employed to recover Ni, W, and Al from spent HYC catalysts. The effects of temperature, leaching time, solid-to-liquid ratio, and stirring speed on metal dissolution were systematically examined. Kinetic analyses were performed to identify the rate-controlling mechanisms governing the leaching behavior of each metal. Findings: The results reveal distinct kinetic behaviors for Ni, W, and Al during leaching, indicating different controlling mechanisms. The ChCl:PTSA system effectively suppressed tungstic acid formation and enabled high metal recoveries under mild operating conditions. These findings demonstrate the strong potential of ChCl:PTSA as a sustainable and efficient leaching medium for the recycling of W-based spent hydrocracking catalysts.